package com.kk.springcloud.lb;

import org.springframework.cloud.client.ServiceInstance;
import org.springframework.stereotype.Component;
import java.util.List;
import java.util.concurrent.atomic.AtomicInteger;

@Component
public class MyLB implements LoadBalancer {

    private AtomicInteger atomicInteger = new AtomicInteger (0);

    @Override
    public ServiceInstance instances(List<ServiceInstance> serviceInstances) {
        int index = getAndIncrement ( ) % serviceInstances.size ( );
        return serviceInstances.get (index);
    }

    public final int getAndIncrement() {
        int current;
        int next;
        do {
            current = this.atomicInteger.get ( );
            next = current >= 2147483647 ? 0 : current + 1;
        } while (!this.atomicInteger.compareAndSet (current, next));
        System.out.println ("*****next: " + next);
        return next;
    }
}
